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Removing and replacing fork seals on a Yamaha TTR250

There is quite a lot of work involved and it is essential that you have the workshop manual to hand for full details of the procedures, torque settings, etc.

Before you start, make sure that the bike is safely on a stand and at a comfortable working height - if at all possible.

Pic 1 Buy the correct fork oil seals. Use OE only and don't forget new dust seals if not using fork gaiters.


Pic 2 Blown fork seals


Pic 3 Push down hard on forks and loosen this 14mm hex nut on both forks before dismantling


Pic 4 & 5 Loosen brake caliper bolts and all fork clamp bolts

Pic 6 Pull stanchion down and clamp tight again in lower yoke; this enables you to
loosen top stanchion nut without having to disturb handlebars etc ( same for
installing as well )


pic 7 & 8 Unscrew fork top ( it isn't under any pressure once you have let the air out from the top valve ) and drain oil...messy so have well covered area.




pic 9 & 10 Remove wire clip and then remove dust seal - best replacing the dust seal
as well ( I elected for fork gaiters instead of the dust seal )

pic 11 That is the oil seal - try to get it out with a seal puller first


pic 12 If no seal puller then unscrew bottom hex nut that you initially loosed
and remove bottom fitting (all one piece )


pic 13 Pull fork leg very firmly a few times until seal and slider come out..takes a bit of effort.


pic 14 Make a homemade plate with a 14mm slot to hold top of fork from spring and unbolt
fork top. remove spring and clean all. IMPORTANT...the small fork slider has to be put in AFTER you have slotted the stanchion in place ( simply slide it over and down the stanchion...

I used a heat gun on the fork leg to help tap the slider back in place; then put metal spacer over slider ( this is where the seal will sit on).

WARNING:- if slider put back into place BEFORE stanchion is put back in, then stanchion won't re-fit and it will take a lot of effort getting that slider back out again !!

Lube new oil seal and carefully slot and lower down stanchion. Top up each leg ( I used 10w ) with 550cc of fork oil. Feed spring back into leg and re-attach the top spacer and fork top. Use some string attached to the top of the damper rod to put it up through the spring if needed.


Pic 15 Nice new seals


Pic 16 Up and running :-)


Take your time, allow about 2 hrs :-)

Good luck! I hope the pics help.

Author and photographer: Kenny Cox, Wirral, England